Much of our current understanding of the functional role played by non-visual (extraretinal) eye position information in the perception of motion and direction is based on studies of the ability to control eye position in the dark or on the ability to set a single target in a reference position in the absence of visual reference marks. The accuracy of the extraretinal signal measured in this manner is too poor to account for the accuracy of many of our visual spatial perceptions and visuomotor coordinations. The proposed research adopts the view that prior descriptions were obtained under conditions where variation in other parameters could be reflected as inaccuracy in the extraretinal signal. The object of the proposed research is to provide a description of the way in which just extraretinal eye position information contributes to our visual spatial perceptions. The strategy involves disrupting extraretinal information by placing lesions in central nervous structures implicated as essential to the normal processing of this signal (beginning with the frontal eye fields). Following lesions, a search will be made for a specific loss of extraretinal eye position information. Subsequently, I will examine the consequences of disrupting extraretinal eye position information on psychophysical judgements of motion and direction to provide much needed information on the accuracy and importance of this signal to our visual spatial perceptions. In addition, this research will do much to further our understanding of the mystery of the function of the frontal eye fields.